Study On The The Inorganic Microcapsules Modified Polyacrylate Emulsion And Its Anticorrosive Protiepers For Metal

Metal corrosion has caused great loss to the national economy.In order to prevent metal corrosion,coating protection has been often used for metal corrosion protection.Polyacrylate emulsions,as a waterborne coating,are widely used in coating materials.However,its application in anticorrosion coatings is limited due to slow film formation rate,poor film density,low hardness,high water and oxygen permeation rate.Based on this,in this study core-shell polyacrylate emulsions with good anticorrosive performances are prepared firstly by semi-continuous seed emulsion polymerization by introducing functional monomers and crosslinking monomers.Then,the inorganic microcapsules are formed by inorganic nanoparticles with anticorrosive properties coated corrosion inhibitor.Finally,polyacrylate/inorganic microcapsules composite emulsions are prepared by polyacrylate emulsion modified with inorganic microcapsules.The composite emulsions are first coated on the surface of the metal substrate via the brush coating method,and then the polyacrylate emulsion and the inorganic microcapsules are coated on the surface of the metal substrate to form polyacrylate/composite microcapsules coatings via layer by layer sparying method,respecitively.Later,anticorrosion performance of the coatings is studied.Characterization results reveal that the core-shell polyacrylate emulsion is successfully synthesized by semi-continuous seed emulsion polymerization.The size of the synthesized emulsion is about 100 nm,and the latex particles are uniformly dispersed.When the dosage of initiator is 3%,core-shell ratio is 3.5:6.5,hard and soft monomer ratio is 1.7:1,the dosage of acrylic acid is 2%,the dosage of hydroxyl ethyl acrylate is 2%,the dosage of methyl acrylic glycidyl ester is 4%,the dosage of hydroxyl phosphate ester is 4%,respectively,the polymerization system exhibits the characteristics of good stability,less gel,high conversion rate,and good film forming property.The polyacrylate emulsion coating formed on the metal surface shows well pencil hardness(2H),high adhesion(0),no flash erosion,and excellent anti-corrosion property.Through the screening of inorganic nanoparticles,BTA@ZnO microcapsules with preservative efficacy are successfully prepared by direct encapsulation.The morphology of the microcapsules is rod-shaped,ranging from 30 to 100 nm in diameter and 200 to 800 nm in length.When the dosage of emulsifier sodium dodecyl sulfate is 0.8%,the amount of inhibitor is 1.5%,and the amount of zinc source is 3%,the amount of BTA@ZnO microcapsules is 1%,respectively,the composite coating shows good comprehensive performance.After polyacrylate and BTA@ZnO microcapsule and polyacrylate/BTA@ZnO microcapsule composite emulsion are applied on the surface of tinplate,the water resistance,salt water resistance and salt spray resistance of the composite coating are better than those of other coatings,and which shows excellent anticorrosion effects.